Treatment of congestive heart failure.

In treating heart failure, the physician must remain cognizant of pathophysiology as he prescribes and monitors therapy. In addition to seeking underlying and precipitating causes of the patient's heart failure, he must treat the congestive state by enhancing myocardial contractility, controlling excessive fluid retention, and reducing afterload. Figure 7 summarizes the theoretical shifts on a patient's left ventricular function curves that might occur with therapy. Left ventricular function might move from point A to point B with diuretic therapy, but overdiuresis could aggravate symptoms of low cardiac output, including postural hypotension. Digitalis would effect a shift from A to C. Isosorbide dinitrate would produce a shift from A to D in a patient not on digitalis and from C to D in a patient already receiving digitalis. Isosorbide dinitrate, in conjunction with more usual therapeutic measures, has proved clinically beneficial in the treatment of heart failure.